Combine the water and orange peel in a small saucepan. Sprinkle in the gelatin and heat over low heat, stirring constantly, until the gelatin has dissolved. Remove from heat, discard the orange zest, and pour in the Campari, vermouth, and gin.

Pour into a loaf pan (I used as many shot glasses as I had first, then poured the rest into the pan) and chill until set. Unmold, slice into squares, and kick your party up a notch!